Not unique at all. People have been using them on cruising boats and large sailboats for years. I have had them on multiple large sailboats that stayed in the water and they work great. Most are not going to be able to bring back a dead battery, but they are great for maintenance charging between uses. I did have one of the large ones with a controller and that one kept a 105 amp deep cycle charged even if we ran it dry. It would take 2-3 days to be back to 100%. I think that one was a 12 or 15 amp.